1 /* $NetBSD: ip_output.c,v 1.133 2004/06/01 05:06:56 itojun Exp $ */ 2 3 /* 4 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the project nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 */ 31 32 /*- 33 * Copyright (c) 1998 The NetBSD Foundation, Inc. 34 * All rights reserved. 35 * 36 * This code is derived from software contributed to The NetBSD Foundation 37 * by Public Access Networks Corporation ("Panix"). It was developed under 38 * contract to Panix by Eric Haszlakiewicz and Thor Lancelot Simon. 39 * 40 * Redistribution and use in source and binary forms, with or without 41 * modification, are permitted provided that the following conditions 42 * are met: 43 * 1. Redistributions of source code must retain the above copyright 44 * notice, this list of conditions and the following disclaimer. 45 * 2. Redistributions in binary form must reproduce the above copyright 46 * notice, this list of conditions and the following disclaimer in the 47 * documentation and/or other materials provided with the distribution. 48 * 3. All advertising materials mentioning features or use of this software 49 * must display the following acknowledgement: 50 * This product includes software developed by the NetBSD 51 * Foundation, Inc. and its contributors. 52 * 4. Neither the name of The NetBSD Foundation nor the names of its 53 * contributors may be used to endorse or promote products derived 54 * from this software without specific prior written permission. 55 * 56 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 57 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 58 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 59 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 60 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 61 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 62 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 63 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 64 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 65 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 66 * POSSIBILITY OF SUCH DAMAGE. 67 */ 68 69 /* 70 * Copyright (c) 1982, 1986, 1988, 1990, 1993 71 * The Regents of the University of California. All rights reserved. 72 * 73 * Redistribution and use in source and binary forms, with or without 74 * modification, are permitted provided that the following conditions 75 * are met: 76 * 1. Redistributions of source code must retain the above copyright 77 * notice, this list of conditions and the following disclaimer. 78 * 2. Redistributions in binary form must reproduce the above copyright 79 * notice, this list of conditions and the following disclaimer in the 80 * documentation and/or other materials provided with the distribution. 81 * 3. Neither the name of the University nor the names of its contributors 82 * may be used to endorse or promote products derived from this software 83 * without specific prior written permission. 84 * 85 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 86 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 87 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 88 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 89 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 90 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 91 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 92 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 93 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 94 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 95 * SUCH DAMAGE. 96 * 97 * @(#)ip_output.c 8.3 (Berkeley) 1/21/94 98 */ 99 100 #include <sys/cdefs.h> 101 __KERNEL_RCSID(0, "$NetBSD: ip_output.c,v 1.133 2004/06/01 05:06:56 itojun Exp $"); 102 103 #include "opt_pfil_hooks.h" 104 #include "opt_inet.h" 105 #include "opt_ipsec.h" 106 #include "opt_mrouting.h" 107 108 #include <sys/param.h> 109 #include <sys/malloc.h> 110 #include <sys/mbuf.h> 111 #include <sys/errno.h> 112 #include <sys/protosw.h> 113 #include <sys/socket.h> 114 #include <sys/socketvar.h> 115 #ifdef FAST_IPSEC 116 #include <sys/domain.h> 117 #endif 118 #include <sys/systm.h> 119 #include <sys/proc.h> 120 121 #include <net/if.h> 122 #include <net/route.h> 123 #include <net/pfil.h> 124 125 #include <netinet/in.h> 126 #include <netinet/in_systm.h> 127 #include <netinet/ip.h> 128 #include <netinet/in_pcb.h> 129 #include <netinet/in_var.h> 130 #include <netinet/ip_var.h> 131 132 #ifdef MROUTING 133 #include <netinet/ip_mroute.h> 134 #endif 135 136 #include <machine/stdarg.h> 137 138 #ifdef IPSEC 139 #include <netinet6/ipsec.h> 140 #include <netkey/key.h> 141 #include <netkey/key_debug.h> 142 #endif /*IPSEC*/ 143 144 #ifdef FAST_IPSEC 145 #include <netipsec/ipsec.h> 146 #include <netipsec/key.h> 147 #include <netipsec/xform.h> 148 #endif /* FAST_IPSEC*/ 149 150 static struct mbuf *ip_insertoptions __P((struct mbuf *, struct mbuf *, int *)); 151 static struct ifnet *ip_multicast_if __P((struct in_addr *, int *)); 152 static void ip_mloopback 153 __P((struct ifnet *, struct mbuf *, struct sockaddr_in *)); 154 155 #ifdef PFIL_HOOKS 156 extern struct pfil_head inet_pfil_hook; /* XXX */ 157 #endif 158 159 /* 160 * IP output. The packet in mbuf chain m contains a skeletal IP 161 * header (with len, off, ttl, proto, tos, src, dst). 162 * The mbuf chain containing the packet will be freed. 163 * The mbuf opt, if present, will not be freed. 164 */ 165 int 166 ip_output(struct mbuf *m0, ...) 167 { 168 struct ip *ip; 169 struct ifnet *ifp; 170 struct mbuf *m = m0; 171 int hlen = sizeof (struct ip); 172 int len, error = 0; 173 struct route iproute; 174 struct sockaddr_in *dst; 175 struct in_ifaddr *ia; 176 struct mbuf *opt; 177 struct route *ro; 178 int flags, sw_csum; 179 int *mtu_p; 180 u_long mtu; 181 struct ip_moptions *imo; 182 struct socket *so; 183 va_list ap; 184 #ifdef IPSEC 185 struct secpolicy *sp = NULL; 186 #endif /*IPSEC*/ 187 #ifdef FAST_IPSEC 188 struct inpcb *inp; 189 struct m_tag *mtag; 190 struct secpolicy *sp = NULL; 191 struct tdb_ident *tdbi; 192 int s; 193 #endif 194 u_int16_t ip_len; 195 196 len = 0; 197 va_start(ap, m0); 198 opt = va_arg(ap, struct mbuf *); 199 ro = va_arg(ap, struct route *); 200 flags = va_arg(ap, int); 201 imo = va_arg(ap, struct ip_moptions *); 202 so = va_arg(ap, struct socket *); 203 if (flags & IP_RETURNMTU) 204 mtu_p = va_arg(ap, int *); 205 else 206 mtu_p = NULL; 207 va_end(ap); 208 209 MCLAIM(m, &ip_tx_mowner); 210 #ifdef FAST_IPSEC 211 if (so != NULL && so->so_proto->pr_domain->dom_family == AF_INET) 212 inp = (struct inpcb *)so->so_pcb; 213 else 214 inp = NULL; 215 #endif /* FAST_IPSEC */ 216 217 #ifdef DIAGNOSTIC 218 if ((m->m_flags & M_PKTHDR) == 0) 219 panic("ip_output no HDR"); 220 #endif 221 if (opt) { 222 m = ip_insertoptions(m, opt, &len); 223 if (len >= sizeof(struct ip)) 224 hlen = len; 225 } 226 ip = mtod(m, struct ip *); 227 /* 228 * Fill in IP header. 229 */ 230 if ((flags & (IP_FORWARDING|IP_RAWOUTPUT)) == 0) { 231 ip->ip_v = IPVERSION; 232 ip->ip_off = htons(0); 233 ip->ip_id = ip_newid(); 234 ip->ip_hl = hlen >> 2; 235 ipstat.ips_localout++; 236 } else { 237 hlen = ip->ip_hl << 2; 238 } 239 /* 240 * Route packet. 241 */ 242 if (ro == 0) { 243 ro = &iproute; 244 bzero((caddr_t)ro, sizeof (*ro)); 245 } 246 dst = satosin(&ro->ro_dst); 247 /* 248 * If there is a cached route, 249 * check that it is to the same destination 250 * and is still up. If not, free it and try again. 251 * The address family should also be checked in case of sharing the 252 * cache with IPv6. 253 */ 254 if (ro->ro_rt && ((ro->ro_rt->rt_flags & RTF_UP) == 0 || 255 dst->sin_family != AF_INET || 256 !in_hosteq(dst->sin_addr, ip->ip_dst))) { 257 RTFREE(ro->ro_rt); 258 ro->ro_rt = (struct rtentry *)0; 259 } 260 if (ro->ro_rt == 0) { 261 bzero(dst, sizeof(*dst)); 262 dst->sin_family = AF_INET; 263 dst->sin_len = sizeof(*dst); 264 dst->sin_addr = ip->ip_dst; 265 } 266 /* 267 * If routing to interface only, 268 * short circuit routing lookup. 269 */ 270 if (flags & IP_ROUTETOIF) { 271 if ((ia = ifatoia(ifa_ifwithladdr(sintosa(dst)))) == 0) { 272 ipstat.ips_noroute++; 273 error = ENETUNREACH; 274 goto bad; 275 } 276 ifp = ia->ia_ifp; 277 mtu = ifp->if_mtu; 278 ip->ip_ttl = 1; 279 } else if ((IN_MULTICAST(ip->ip_dst.s_addr) || 280 ip->ip_dst.s_addr == INADDR_BROADCAST) && 281 imo != NULL && imo->imo_multicast_ifp != NULL) { 282 ifp = imo->imo_multicast_ifp; 283 mtu = ifp->if_mtu; 284 IFP_TO_IA(ifp, ia); 285 } else { 286 if (ro->ro_rt == 0) 287 rtalloc(ro); 288 if (ro->ro_rt == 0) { 289 ipstat.ips_noroute++; 290 error = EHOSTUNREACH; 291 goto bad; 292 } 293 ia = ifatoia(ro->ro_rt->rt_ifa); 294 ifp = ro->ro_rt->rt_ifp; 295 if ((mtu = ro->ro_rt->rt_rmx.rmx_mtu) == 0) 296 mtu = ifp->if_mtu; 297 ro->ro_rt->rt_use++; 298 if (ro->ro_rt->rt_flags & RTF_GATEWAY) 299 dst = satosin(ro->ro_rt->rt_gateway); 300 } 301 if (IN_MULTICAST(ip->ip_dst.s_addr) || 302 (ip->ip_dst.s_addr == INADDR_BROADCAST)) { 303 struct in_multi *inm; 304 305 m->m_flags |= (ip->ip_dst.s_addr == INADDR_BROADCAST) ? 306 M_BCAST : M_MCAST; 307 /* 308 * IP destination address is multicast. Make sure "dst" 309 * still points to the address in "ro". (It may have been 310 * changed to point to a gateway address, above.) 311 */ 312 dst = satosin(&ro->ro_dst); 313 /* 314 * See if the caller provided any multicast options 315 */ 316 if (imo != NULL) 317 ip->ip_ttl = imo->imo_multicast_ttl; 318 else 319 ip->ip_ttl = IP_DEFAULT_MULTICAST_TTL; 320 321 /* 322 * if we don't know the outgoing ifp yet, we can't generate 323 * output 324 */ 325 if (!ifp) { 326 ipstat.ips_noroute++; 327 error = ENETUNREACH; 328 goto bad; 329 } 330 331 /* 332 * If the packet is multicast or broadcast, confirm that 333 * the outgoing interface can transmit it. 334 */ 335 if (((m->m_flags & M_MCAST) && 336 (ifp->if_flags & IFF_MULTICAST) == 0) || 337 ((m->m_flags & M_BCAST) && 338 (ifp->if_flags & (IFF_BROADCAST|IFF_POINTOPOINT)) == 0)) { 339 ipstat.ips_noroute++; 340 error = ENETUNREACH; 341 goto bad; 342 } 343 /* 344 * If source address not specified yet, use an address 345 * of outgoing interface. 346 */ 347 if (in_nullhost(ip->ip_src)) { 348 struct in_ifaddr *ia; 349 350 IFP_TO_IA(ifp, ia); 351 if (!ia) { 352 error = EADDRNOTAVAIL; 353 goto bad; 354 } 355 ip->ip_src = ia->ia_addr.sin_addr; 356 } 357 358 IN_LOOKUP_MULTI(ip->ip_dst, ifp, inm); 359 if (inm != NULL && 360 (imo == NULL || imo->imo_multicast_loop)) { 361 /* 362 * If we belong to the destination multicast group 363 * on the outgoing interface, and the caller did not 364 * forbid loopback, loop back a copy. 365 */ 366 ip_mloopback(ifp, m, dst); 367 } 368 #ifdef MROUTING 369 else { 370 /* 371 * If we are acting as a multicast router, perform 372 * multicast forwarding as if the packet had just 373 * arrived on the interface to which we are about 374 * to send. The multicast forwarding function 375 * recursively calls this function, using the 376 * IP_FORWARDING flag to prevent infinite recursion. 377 * 378 * Multicasts that are looped back by ip_mloopback(), 379 * above, will be forwarded by the ip_input() routine, 380 * if necessary. 381 */ 382 extern struct socket *ip_mrouter; 383 384 if (ip_mrouter && (flags & IP_FORWARDING) == 0) { 385 if (ip_mforward(m, ifp) != 0) { 386 m_freem(m); 387 goto done; 388 } 389 } 390 } 391 #endif 392 /* 393 * Multicasts with a time-to-live of zero may be looped- 394 * back, above, but must not be transmitted on a network. 395 * Also, multicasts addressed to the loopback interface 396 * are not sent -- the above call to ip_mloopback() will 397 * loop back a copy if this host actually belongs to the 398 * destination group on the loopback interface. 399 */ 400 if (ip->ip_ttl == 0 || (ifp->if_flags & IFF_LOOPBACK) != 0) { 401 m_freem(m); 402 goto done; 403 } 404 405 goto sendit; 406 } 407 #ifndef notdef 408 /* 409 * If source address not specified yet, use address 410 * of outgoing interface. 411 */ 412 if (in_nullhost(ip->ip_src)) 413 ip->ip_src = ia->ia_addr.sin_addr; 414 #endif 415 416 /* 417 * packets with Class-D address as source are not valid per 418 * RFC 1112 419 */ 420 if (IN_MULTICAST(ip->ip_src.s_addr)) { 421 ipstat.ips_odropped++; 422 error = EADDRNOTAVAIL; 423 goto bad; 424 } 425 426 /* 427 * Look for broadcast address and 428 * and verify user is allowed to send 429 * such a packet. 430 */ 431 if (in_broadcast(dst->sin_addr, ifp)) { 432 if ((ifp->if_flags & IFF_BROADCAST) == 0) { 433 error = EADDRNOTAVAIL; 434 goto bad; 435 } 436 if ((flags & IP_ALLOWBROADCAST) == 0) { 437 error = EACCES; 438 goto bad; 439 } 440 /* don't allow broadcast messages to be fragmented */ 441 if (ntohs(ip->ip_len) > ifp->if_mtu) { 442 error = EMSGSIZE; 443 goto bad; 444 } 445 m->m_flags |= M_BCAST; 446 } else 447 m->m_flags &= ~M_BCAST; 448 449 sendit: 450 /* 451 * If we're doing Path MTU Discovery, we need to set DF unless 452 * the route's MTU is locked. 453 */ 454 if ((flags & IP_MTUDISC) != 0 && ro->ro_rt != NULL && 455 (ro->ro_rt->rt_rmx.rmx_locks & RTV_MTU) == 0) 456 ip->ip_off |= htons(IP_DF); 457 458 /* Remember the current ip_len */ 459 ip_len = ntohs(ip->ip_len); 460 461 #ifdef IPSEC 462 /* get SP for this packet */ 463 if (so == NULL) 464 sp = ipsec4_getpolicybyaddr(m, IPSEC_DIR_OUTBOUND, 465 flags, &error); 466 else { 467 if (IPSEC_PCB_SKIP_IPSEC(sotoinpcb_hdr(so)->inph_sp, 468 IPSEC_DIR_OUTBOUND)) 469 goto skip_ipsec; 470 sp = ipsec4_getpolicybysock(m, IPSEC_DIR_OUTBOUND, so, &error); 471 } 472 473 if (sp == NULL) { 474 ipsecstat.out_inval++; 475 goto bad; 476 } 477 478 error = 0; 479 480 /* check policy */ 481 switch (sp->policy) { 482 case IPSEC_POLICY_DISCARD: 483 /* 484 * This packet is just discarded. 485 */ 486 ipsecstat.out_polvio++; 487 goto bad; 488 489 case IPSEC_POLICY_BYPASS: 490 case IPSEC_POLICY_NONE: 491 /* no need to do IPsec. */ 492 goto skip_ipsec; 493 494 case IPSEC_POLICY_IPSEC: 495 if (sp->req == NULL) { 496 /* XXX should be panic ? */ 497 printf("ip_output: No IPsec request specified.\n"); 498 error = EINVAL; 499 goto bad; 500 } 501 break; 502 503 case IPSEC_POLICY_ENTRUST: 504 default: 505 printf("ip_output: Invalid policy found. %d\n", sp->policy); 506 } 507 508 /* 509 * ipsec4_output() expects ip_len and ip_off in network 510 * order. They have been set to network order above. 511 */ 512 513 { 514 struct ipsec_output_state state; 515 bzero(&state, sizeof(state)); 516 state.m = m; 517 if (flags & IP_ROUTETOIF) { 518 state.ro = &iproute; 519 bzero(&iproute, sizeof(iproute)); 520 } else 521 state.ro = ro; 522 state.dst = (struct sockaddr *)dst; 523 524 /* 525 * We can't defer the checksum of payload data if 526 * we're about to encrypt/authenticate it. 527 * 528 * XXX When we support crypto offloading functions of 529 * XXX network interfaces, we need to reconsider this, 530 * XXX since it's likely that they'll support checksumming, 531 * XXX as well. 532 */ 533 if (m->m_pkthdr.csum_flags & (M_CSUM_TCPv4|M_CSUM_UDPv4)) { 534 in_delayed_cksum(m); 535 m->m_pkthdr.csum_flags &= ~(M_CSUM_TCPv4|M_CSUM_UDPv4); 536 } 537 538 error = ipsec4_output(&state, sp, flags); 539 540 m = state.m; 541 if (flags & IP_ROUTETOIF) { 542 /* 543 * if we have tunnel mode SA, we may need to ignore 544 * IP_ROUTETOIF. 545 */ 546 if (state.ro != &iproute || state.ro->ro_rt != NULL) { 547 flags &= ~IP_ROUTETOIF; 548 ro = state.ro; 549 } 550 } else 551 ro = state.ro; 552 dst = (struct sockaddr_in *)state.dst; 553 if (error) { 554 /* mbuf is already reclaimed in ipsec4_output. */ 555 m0 = NULL; 556 switch (error) { 557 case EHOSTUNREACH: 558 case ENETUNREACH: 559 case EMSGSIZE: 560 case ENOBUFS: 561 case ENOMEM: 562 break; 563 default: 564 printf("ip4_output (ipsec): error code %d\n", error); 565 /*fall through*/ 566 case ENOENT: 567 /* don't show these error codes to the user */ 568 error = 0; 569 break; 570 } 571 goto bad; 572 } 573 574 /* be sure to update variables that are affected by ipsec4_output() */ 575 ip = mtod(m, struct ip *); 576 hlen = ip->ip_hl << 2; 577 ip_len = ntohs(ip->ip_len); 578 579 if (ro->ro_rt == NULL) { 580 if ((flags & IP_ROUTETOIF) == 0) { 581 printf("ip_output: " 582 "can't update route after IPsec processing\n"); 583 error = EHOSTUNREACH; /*XXX*/ 584 goto bad; 585 } 586 } else { 587 /* nobody uses ia beyond here */ 588 if (state.encap) { 589 ifp = ro->ro_rt->rt_ifp; 590 if ((mtu = ro->ro_rt->rt_rmx.rmx_mtu) == 0) 591 mtu = ifp->if_mtu; 592 } 593 } 594 } 595 skip_ipsec: 596 #endif /*IPSEC*/ 597 #ifdef FAST_IPSEC 598 /* 599 * Check the security policy (SP) for the packet and, if 600 * required, do IPsec-related processing. There are two 601 * cases here; the first time a packet is sent through 602 * it will be untagged and handled by ipsec4_checkpolicy. 603 * If the packet is resubmitted to ip_output (e.g. after 604 * AH, ESP, etc. processing), there will be a tag to bypass 605 * the lookup and related policy checking. 606 */ 607 mtag = m_tag_find(m, PACKET_TAG_IPSEC_PENDING_TDB, NULL); 608 s = splsoftnet(); 609 if (mtag != NULL) { 610 tdbi = (struct tdb_ident *)(mtag + 1); 611 sp = ipsec_getpolicy(tdbi, IPSEC_DIR_OUTBOUND); 612 if (sp == NULL) 613 error = -EINVAL; /* force silent drop */ 614 m_tag_delete(m, mtag); 615 } else { 616 if (inp != NULL && 617 IPSEC_PCB_SKIP_IPSEC(inp->inp_sp, IPSEC_DIR_OUTBOUND)) 618 goto spd_done; 619 sp = ipsec4_checkpolicy(m, IPSEC_DIR_OUTBOUND, flags, 620 &error, inp); 621 } 622 /* 623 * There are four return cases: 624 * sp != NULL apply IPsec policy 625 * sp == NULL, error == 0 no IPsec handling needed 626 * sp == NULL, error == -EINVAL discard packet w/o error 627 * sp == NULL, error != 0 discard packet, report error 628 */ 629 if (sp != NULL) { 630 /* Loop detection, check if ipsec processing already done */ 631 IPSEC_ASSERT(sp->req != NULL, ("ip_output: no ipsec request")); 632 for (mtag = m_tag_first(m); mtag != NULL; 633 mtag = m_tag_next(m, mtag)) { 634 #ifdef MTAG_ABI_COMPAT 635 if (mtag->m_tag_cookie != MTAG_ABI_COMPAT) 636 continue; 637 #endif 638 if (mtag->m_tag_id != PACKET_TAG_IPSEC_OUT_DONE && 639 mtag->m_tag_id != PACKET_TAG_IPSEC_OUT_CRYPTO_NEEDED) 640 continue; 641 /* 642 * Check if policy has an SA associated with it. 643 * This can happen when an SP has yet to acquire 644 * an SA; e.g. on first reference. If it occurs, 645 * then we let ipsec4_process_packet do its thing. 646 */ 647 if (sp->req->sav == NULL) 648 break; 649 tdbi = (struct tdb_ident *)(mtag + 1); 650 if (tdbi->spi == sp->req->sav->spi && 651 tdbi->proto == sp->req->sav->sah->saidx.proto && 652 bcmp(&tdbi->dst, &sp->req->sav->sah->saidx.dst, 653 sizeof (union sockaddr_union)) == 0) { 654 /* 655 * No IPsec processing is needed, free 656 * reference to SP. 657 * 658 * NB: null pointer to avoid free at 659 * done: below. 660 */ 661 KEY_FREESP(&sp), sp = NULL; 662 splx(s); 663 goto spd_done; 664 } 665 } 666 667 /* 668 * Do delayed checksums now because we send before 669 * this is done in the normal processing path. 670 */ 671 if (m->m_pkthdr.csum_flags & (M_CSUM_TCPv4|M_CSUM_UDPv4)) { 672 in_delayed_cksum(m); 673 m->m_pkthdr.csum_flags &= ~(M_CSUM_TCPv4|M_CSUM_UDPv4); 674 } 675 676 #ifdef __FreeBSD__ 677 ip->ip_len = htons(ip->ip_len); 678 ip->ip_off = htons(ip->ip_off); 679 #endif 680 681 /* NB: callee frees mbuf */ 682 error = ipsec4_process_packet(m, sp->req, flags, 0); 683 /* 684 * Preserve KAME behaviour: ENOENT can be returned 685 * when an SA acquire is in progress. Don't propagate 686 * this to user-level; it confuses applications. 687 * 688 * XXX this will go away when the SADB is redone. 689 */ 690 if (error == ENOENT) 691 error = 0; 692 splx(s); 693 goto done; 694 } else { 695 splx(s); 696 697 if (error != 0) { 698 /* 699 * Hack: -EINVAL is used to signal that a packet 700 * should be silently discarded. This is typically 701 * because we asked key management for an SA and 702 * it was delayed (e.g. kicked up to IKE). 703 */ 704 if (error == -EINVAL) 705 error = 0; 706 goto bad; 707 } else { 708 /* No IPsec processing for this packet. */ 709 } 710 #ifdef notyet 711 /* 712 * If deferred crypto processing is needed, check that 713 * the interface supports it. 714 */ 715 mtag = m_tag_find(m, PACKET_TAG_IPSEC_OUT_CRYPTO_NEEDED, NULL); 716 if (mtag != NULL && (ifp->if_capenable & IFCAP_IPSEC) == 0) { 717 /* notify IPsec to do its own crypto */ 718 ipsp_skipcrypto_unmark((struct tdb_ident *)(mtag + 1)); 719 error = EHOSTUNREACH; 720 goto bad; 721 } 722 #endif 723 } 724 spd_done: 725 #endif /* FAST_IPSEC */ 726 727 #ifdef PFIL_HOOKS 728 /* 729 * Run through list of hooks for output packets. 730 */ 731 if ((error = pfil_run_hooks(&inet_pfil_hook, &m, ifp, PFIL_OUT)) != 0) 732 goto done; 733 if (m == NULL) 734 goto done; 735 736 ip = mtod(m, struct ip *); 737 hlen = ip->ip_hl << 2; 738 #endif /* PFIL_HOOKS */ 739 740 m->m_pkthdr.csum_flags |= M_CSUM_IPv4; 741 sw_csum = m->m_pkthdr.csum_flags & ~ifp->if_csum_flags_tx; 742 /* 743 * If small enough for mtu of path, can just send directly. 744 */ 745 if (ip_len <= mtu) { 746 #if IFA_STATS 747 /* 748 * search for the source address structure to 749 * maintain output statistics. 750 */ 751 INADDR_TO_IA(ip->ip_src, ia); 752 if (ia) 753 ia->ia_ifa.ifa_data.ifad_outbytes += ip_len; 754 #endif 755 /* 756 * Always initialize the sum to 0! Some HW assisted 757 * checksumming requires this. 758 */ 759 ip->ip_sum = 0; 760 761 /* 762 * Perform any checksums that the hardware can't do 763 * for us. 764 * 765 * XXX Does any hardware require the {th,uh}_sum 766 * XXX fields to be 0? 767 */ 768 if (sw_csum & M_CSUM_IPv4) { 769 ip->ip_sum = in_cksum(m, hlen); 770 m->m_pkthdr.csum_flags &= ~M_CSUM_IPv4; 771 } 772 if (sw_csum & (M_CSUM_TCPv4|M_CSUM_UDPv4)) { 773 in_delayed_cksum(m); 774 m->m_pkthdr.csum_flags &= ~(M_CSUM_TCPv4|M_CSUM_UDPv4); 775 } 776 777 #ifdef IPSEC 778 /* clean ipsec history once it goes out of the node */ 779 ipsec_delaux(m); 780 #endif 781 error = (*ifp->if_output)(ifp, m, sintosa(dst), ro->ro_rt); 782 goto done; 783 } 784 785 /* 786 * We can't use HW checksumming if we're about to 787 * to fragment the packet. 788 * 789 * XXX Some hardware can do this. 790 */ 791 if (m->m_pkthdr.csum_flags & (M_CSUM_TCPv4|M_CSUM_UDPv4)) { 792 in_delayed_cksum(m); 793 m->m_pkthdr.csum_flags &= ~(M_CSUM_TCPv4|M_CSUM_UDPv4); 794 } 795 796 /* 797 * Too large for interface; fragment if possible. 798 * Must be able to put at least 8 bytes per fragment. 799 */ 800 if (ntohs(ip->ip_off) & IP_DF) { 801 if (flags & IP_RETURNMTU) 802 *mtu_p = mtu; 803 error = EMSGSIZE; 804 ipstat.ips_cantfrag++; 805 goto bad; 806 } 807 808 error = ip_fragment(m, ifp, mtu); 809 if (error) { 810 m = NULL; 811 goto bad; 812 } 813 814 for (; m; m = m0) { 815 m0 = m->m_nextpkt; 816 m->m_nextpkt = 0; 817 if (error == 0) { 818 #if IFA_STATS 819 /* 820 * search for the source address structure to 821 * maintain output statistics. 822 */ 823 INADDR_TO_IA(ip->ip_src, ia); 824 if (ia) { 825 ia->ia_ifa.ifa_data.ifad_outbytes += 826 ntohs(ip->ip_len); 827 } 828 #endif 829 #ifdef IPSEC 830 /* clean ipsec history once it goes out of the node */ 831 ipsec_delaux(m); 832 #endif 833 KASSERT((m->m_pkthdr.csum_flags & 834 (M_CSUM_UDPv4 | M_CSUM_TCPv4)) == 0); 835 error = (*ifp->if_output)(ifp, m, sintosa(dst), 836 ro->ro_rt); 837 } else 838 m_freem(m); 839 } 840 841 if (error == 0) 842 ipstat.ips_fragmented++; 843 done: 844 if (ro == &iproute && (flags & IP_ROUTETOIF) == 0 && ro->ro_rt) { 845 RTFREE(ro->ro_rt); 846 ro->ro_rt = 0; 847 } 848 849 #ifdef IPSEC 850 if (sp != NULL) { 851 KEYDEBUG(KEYDEBUG_IPSEC_STAMP, 852 printf("DP ip_output call free SP:%p\n", sp)); 853 key_freesp(sp); 854 } 855 #endif /* IPSEC */ 856 #ifdef FAST_IPSEC 857 if (sp != NULL) 858 KEY_FREESP(&sp); 859 #endif /* FAST_IPSEC */ 860 861 return (error); 862 bad: 863 m_freem(m); 864 goto done; 865 } 866 867 int 868 ip_fragment(struct mbuf *m, struct ifnet *ifp, u_long mtu) 869 { 870 struct ip *ip, *mhip; 871 struct mbuf *m0; 872 int len, hlen, off; 873 int mhlen, firstlen; 874 struct mbuf **mnext; 875 int sw_csum; 876 int fragments = 0; 877 int s; 878 int error = 0; 879 880 ip = mtod(m, struct ip *); 881 hlen = ip->ip_hl << 2; 882 sw_csum = m->m_pkthdr.csum_flags & ~ifp->if_csum_flags_tx; 883 884 len = (mtu - hlen) &~ 7; 885 if (len < 8) { 886 m_freem(m); 887 return (EMSGSIZE); 888 } 889 890 firstlen = len; 891 mnext = &m->m_nextpkt; 892 893 /* 894 * Loop through length of segment after first fragment, 895 * make new header and copy data of each part and link onto chain. 896 */ 897 m0 = m; 898 mhlen = sizeof (struct ip); 899 for (off = hlen + len; off < ntohs(ip->ip_len); off += len) { 900 MGETHDR(m, M_DONTWAIT, MT_HEADER); 901 if (m == 0) { 902 error = ENOBUFS; 903 ipstat.ips_odropped++; 904 goto sendorfree; 905 } 906 MCLAIM(m, m0->m_owner); 907 *mnext = m; 908 mnext = &m->m_nextpkt; 909 m->m_data += max_linkhdr; 910 mhip = mtod(m, struct ip *); 911 *mhip = *ip; 912 /* we must inherit MCAST and BCAST flags */ 913 m->m_flags |= m0->m_flags & (M_MCAST|M_BCAST); 914 if (hlen > sizeof (struct ip)) { 915 mhlen = ip_optcopy(ip, mhip) + sizeof (struct ip); 916 mhip->ip_hl = mhlen >> 2; 917 } 918 m->m_len = mhlen; 919 mhip->ip_off = ((off - hlen) >> 3) + 920 (ntohs(ip->ip_off) & ~IP_MF); 921 if (ip->ip_off & htons(IP_MF)) 922 mhip->ip_off |= IP_MF; 923 if (off + len >= ntohs(ip->ip_len)) 924 len = ntohs(ip->ip_len) - off; 925 else 926 mhip->ip_off |= IP_MF; 927 HTONS(mhip->ip_off); 928 mhip->ip_len = htons((u_int16_t)(len + mhlen)); 929 m->m_next = m_copy(m0, off, len); 930 if (m->m_next == 0) { 931 error = ENOBUFS; /* ??? */ 932 ipstat.ips_odropped++; 933 goto sendorfree; 934 } 935 m->m_pkthdr.len = mhlen + len; 936 m->m_pkthdr.rcvif = (struct ifnet *)0; 937 mhip->ip_sum = 0; 938 if (sw_csum & M_CSUM_IPv4) { 939 mhip->ip_sum = in_cksum(m, mhlen); 940 KASSERT((m->m_pkthdr.csum_flags & M_CSUM_IPv4) == 0); 941 } else { 942 m->m_pkthdr.csum_flags |= M_CSUM_IPv4; 943 } 944 ipstat.ips_ofragments++; 945 fragments++; 946 } 947 /* 948 * Update first fragment by trimming what's been copied out 949 * and updating header, then send each fragment (in order). 950 */ 951 m = m0; 952 m_adj(m, hlen + firstlen - ntohs(ip->ip_len)); 953 m->m_pkthdr.len = hlen + firstlen; 954 ip->ip_len = htons((u_int16_t)m->m_pkthdr.len); 955 ip->ip_off |= htons(IP_MF); 956 ip->ip_sum = 0; 957 if (sw_csum & M_CSUM_IPv4) { 958 ip->ip_sum = in_cksum(m, hlen); 959 m->m_pkthdr.csum_flags &= ~M_CSUM_IPv4; 960 } else { 961 KASSERT(m->m_pkthdr.csum_flags & M_CSUM_IPv4); 962 } 963 sendorfree: 964 /* 965 * If there is no room for all the fragments, don't queue 966 * any of them. 967 */ 968 s = splnet(); 969 if (ifp->if_snd.ifq_maxlen - ifp->if_snd.ifq_len < fragments && 970 error == 0) { 971 error = ENOBUFS; 972 ipstat.ips_odropped++; 973 IFQ_INC_DROPS(&ifp->if_snd); 974 } 975 splx(s); 976 if (error) { 977 for (m = m0; m; m = m0) { 978 m0 = m->m_nextpkt; 979 m->m_nextpkt = NULL; 980 m_freem(m); 981 } 982 } 983 return (error); 984 } 985 986 /* 987 * Process a delayed payload checksum calculation. 988 */ 989 void 990 in_delayed_cksum(struct mbuf *m) 991 { 992 struct ip *ip; 993 u_int16_t csum, offset; 994 995 ip = mtod(m, struct ip *); 996 offset = ip->ip_hl << 2; 997 csum = in4_cksum(m, 0, offset, ntohs(ip->ip_len) - offset); 998 if (csum == 0 && (m->m_pkthdr.csum_flags & M_CSUM_UDPv4) != 0) 999 csum = 0xffff; 1000 1001 offset += m->m_pkthdr.csum_data; /* checksum offset */ 1002 1003 if ((offset + sizeof(u_int16_t)) > m->m_len) { 1004 /* This happen when ip options were inserted 1005 printf("in_delayed_cksum: pullup len %d off %d proto %d\n", 1006 m->m_len, offset, ip->ip_p); 1007 */ 1008 m_copyback(m, offset, sizeof(csum), (caddr_t) &csum); 1009 } else 1010 *(u_int16_t *)(mtod(m, caddr_t) + offset) = csum; 1011 } 1012 1013 /* 1014 * Determine the maximum length of the options to be inserted; 1015 * we would far rather allocate too much space rather than too little. 1016 */ 1017 1018 u_int 1019 ip_optlen(inp) 1020 struct inpcb *inp; 1021 { 1022 struct mbuf *m = inp->inp_options; 1023 1024 if (m && m->m_len > offsetof(struct ipoption, ipopt_dst)) 1025 return (m->m_len - offsetof(struct ipoption, ipopt_dst)); 1026 else 1027 return 0; 1028 } 1029 1030 1031 /* 1032 * Insert IP options into preformed packet. 1033 * Adjust IP destination as required for IP source routing, 1034 * as indicated by a non-zero in_addr at the start of the options. 1035 */ 1036 static struct mbuf * 1037 ip_insertoptions(m, opt, phlen) 1038 struct mbuf *m; 1039 struct mbuf *opt; 1040 int *phlen; 1041 { 1042 struct ipoption *p = mtod(opt, struct ipoption *); 1043 struct mbuf *n; 1044 struct ip *ip = mtod(m, struct ip *); 1045 unsigned optlen; 1046 1047 optlen = opt->m_len - sizeof(p->ipopt_dst); 1048 if (optlen + ntohs(ip->ip_len) > IP_MAXPACKET) 1049 return (m); /* XXX should fail */ 1050 if (!in_nullhost(p->ipopt_dst)) 1051 ip->ip_dst = p->ipopt_dst; 1052 if (M_READONLY(m) || M_LEADINGSPACE(m) < optlen) { 1053 MGETHDR(n, M_DONTWAIT, MT_HEADER); 1054 if (n == 0) 1055 return (m); 1056 MCLAIM(n, m->m_owner); 1057 M_COPY_PKTHDR(n, m); 1058 m_tag_delete_chain(m, NULL); 1059 m->m_flags &= ~M_PKTHDR; 1060 m->m_len -= sizeof(struct ip); 1061 m->m_data += sizeof(struct ip); 1062 n->m_next = m; 1063 m = n; 1064 m->m_len = optlen + sizeof(struct ip); 1065 m->m_data += max_linkhdr; 1066 bcopy((caddr_t)ip, mtod(m, caddr_t), sizeof(struct ip)); 1067 } else { 1068 m->m_data -= optlen; 1069 m->m_len += optlen; 1070 memmove(mtod(m, caddr_t), ip, sizeof(struct ip)); 1071 } 1072 m->m_pkthdr.len += optlen; 1073 ip = mtod(m, struct ip *); 1074 bcopy((caddr_t)p->ipopt_list, (caddr_t)(ip + 1), (unsigned)optlen); 1075 *phlen = sizeof(struct ip) + optlen; 1076 ip->ip_len = htons(ntohs(ip->ip_len) + optlen); 1077 return (m); 1078 } 1079 1080 /* 1081 * Copy options from ip to jp, 1082 * omitting those not copied during fragmentation. 1083 */ 1084 int 1085 ip_optcopy(ip, jp) 1086 struct ip *ip, *jp; 1087 { 1088 u_char *cp, *dp; 1089 int opt, optlen, cnt; 1090 1091 cp = (u_char *)(ip + 1); 1092 dp = (u_char *)(jp + 1); 1093 cnt = (ip->ip_hl << 2) - sizeof (struct ip); 1094 for (; cnt > 0; cnt -= optlen, cp += optlen) { 1095 opt = cp[0]; 1096 if (opt == IPOPT_EOL) 1097 break; 1098 if (opt == IPOPT_NOP) { 1099 /* Preserve for IP mcast tunnel's LSRR alignment. */ 1100 *dp++ = IPOPT_NOP; 1101 optlen = 1; 1102 continue; 1103 } 1104 #ifdef DIAGNOSTIC 1105 if (cnt < IPOPT_OLEN + sizeof(*cp)) 1106 panic("malformed IPv4 option passed to ip_optcopy"); 1107 #endif 1108 optlen = cp[IPOPT_OLEN]; 1109 #ifdef DIAGNOSTIC 1110 if (optlen < IPOPT_OLEN + sizeof(*cp) || optlen > cnt) 1111 panic("malformed IPv4 option passed to ip_optcopy"); 1112 #endif 1113 /* bogus lengths should have been caught by ip_dooptions */ 1114 if (optlen > cnt) 1115 optlen = cnt; 1116 if (IPOPT_COPIED(opt)) { 1117 bcopy((caddr_t)cp, (caddr_t)dp, (unsigned)optlen); 1118 dp += optlen; 1119 } 1120 } 1121 for (optlen = dp - (u_char *)(jp+1); optlen & 0x3; optlen++) 1122 *dp++ = IPOPT_EOL; 1123 return (optlen); 1124 } 1125 1126 /* 1127 * IP socket option processing. 1128 */ 1129 int 1130 ip_ctloutput(op, so, level, optname, mp) 1131 int op; 1132 struct socket *so; 1133 int level, optname; 1134 struct mbuf **mp; 1135 { 1136 struct inpcb *inp = sotoinpcb(so); 1137 struct mbuf *m = *mp; 1138 int optval = 0; 1139 int error = 0; 1140 #if defined(IPSEC) || defined(FAST_IPSEC) 1141 struct proc *p = curproc; /*XXX*/ 1142 #endif 1143 1144 if (level != IPPROTO_IP) { 1145 error = EINVAL; 1146 if (op == PRCO_SETOPT && *mp) 1147 (void) m_free(*mp); 1148 } else switch (op) { 1149 1150 case PRCO_SETOPT: 1151 switch (optname) { 1152 case IP_OPTIONS: 1153 #ifdef notyet 1154 case IP_RETOPTS: 1155 return (ip_pcbopts(optname, &inp->inp_options, m)); 1156 #else 1157 return (ip_pcbopts(&inp->inp_options, m)); 1158 #endif 1159 1160 case IP_TOS: 1161 case IP_TTL: 1162 case IP_RECVOPTS: 1163 case IP_RECVRETOPTS: 1164 case IP_RECVDSTADDR: 1165 case IP_RECVIF: 1166 if (m == NULL || m->m_len != sizeof(int)) 1167 error = EINVAL; 1168 else { 1169 optval = *mtod(m, int *); 1170 switch (optname) { 1171 1172 case IP_TOS: 1173 inp->inp_ip.ip_tos = optval; 1174 break; 1175 1176 case IP_TTL: 1177 inp->inp_ip.ip_ttl = optval; 1178 break; 1179 #define OPTSET(bit) \ 1180 if (optval) \ 1181 inp->inp_flags |= bit; \ 1182 else \ 1183 inp->inp_flags &= ~bit; 1184 1185 case IP_RECVOPTS: 1186 OPTSET(INP_RECVOPTS); 1187 break; 1188 1189 case IP_RECVRETOPTS: 1190 OPTSET(INP_RECVRETOPTS); 1191 break; 1192 1193 case IP_RECVDSTADDR: 1194 OPTSET(INP_RECVDSTADDR); 1195 break; 1196 1197 case IP_RECVIF: 1198 OPTSET(INP_RECVIF); 1199 break; 1200 } 1201 } 1202 break; 1203 #undef OPTSET 1204 1205 case IP_MULTICAST_IF: 1206 case IP_MULTICAST_TTL: 1207 case IP_MULTICAST_LOOP: 1208 case IP_ADD_MEMBERSHIP: 1209 case IP_DROP_MEMBERSHIP: 1210 error = ip_setmoptions(optname, &inp->inp_moptions, m); 1211 break; 1212 1213 case IP_PORTRANGE: 1214 if (m == 0 || m->m_len != sizeof(int)) 1215 error = EINVAL; 1216 else { 1217 optval = *mtod(m, int *); 1218 1219 switch (optval) { 1220 1221 case IP_PORTRANGE_DEFAULT: 1222 case IP_PORTRANGE_HIGH: 1223 inp->inp_flags &= ~(INP_LOWPORT); 1224 break; 1225 1226 case IP_PORTRANGE_LOW: 1227 inp->inp_flags |= INP_LOWPORT; 1228 break; 1229 1230 default: 1231 error = EINVAL; 1232 break; 1233 } 1234 } 1235 break; 1236 1237 #if defined(IPSEC) || defined(FAST_IPSEC) 1238 case IP_IPSEC_POLICY: 1239 { 1240 caddr_t req = NULL; 1241 size_t len = 0; 1242 int priv = 0; 1243 1244 #ifdef __NetBSD__ 1245 if (p == 0 || suser(p->p_ucred, &p->p_acflag)) 1246 priv = 0; 1247 else 1248 priv = 1; 1249 #else 1250 priv = (in6p->in6p_socket->so_state & SS_PRIV); 1251 #endif 1252 if (m) { 1253 req = mtod(m, caddr_t); 1254 len = m->m_len; 1255 } 1256 error = ipsec4_set_policy(inp, optname, req, len, priv); 1257 break; 1258 } 1259 #endif /*IPSEC*/ 1260 1261 default: 1262 error = ENOPROTOOPT; 1263 break; 1264 } 1265 if (m) 1266 (void)m_free(m); 1267 break; 1268 1269 case PRCO_GETOPT: 1270 switch (optname) { 1271 case IP_OPTIONS: 1272 case IP_RETOPTS: 1273 *mp = m = m_get(M_WAIT, MT_SOOPTS); 1274 MCLAIM(m, so->so_mowner); 1275 if (inp->inp_options) { 1276 m->m_len = inp->inp_options->m_len; 1277 bcopy(mtod(inp->inp_options, caddr_t), 1278 mtod(m, caddr_t), (unsigned)m->m_len); 1279 } else 1280 m->m_len = 0; 1281 break; 1282 1283 case IP_TOS: 1284 case IP_TTL: 1285 case IP_RECVOPTS: 1286 case IP_RECVRETOPTS: 1287 case IP_RECVDSTADDR: 1288 case IP_RECVIF: 1289 case IP_ERRORMTU: 1290 *mp = m = m_get(M_WAIT, MT_SOOPTS); 1291 MCLAIM(m, so->so_mowner); 1292 m->m_len = sizeof(int); 1293 switch (optname) { 1294 1295 case IP_TOS: 1296 optval = inp->inp_ip.ip_tos; 1297 break; 1298 1299 case IP_TTL: 1300 optval = inp->inp_ip.ip_ttl; 1301 break; 1302 1303 case IP_ERRORMTU: 1304 optval = inp->inp_errormtu; 1305 break; 1306 1307 #define OPTBIT(bit) (inp->inp_flags & bit ? 1 : 0) 1308 1309 case IP_RECVOPTS: 1310 optval = OPTBIT(INP_RECVOPTS); 1311 break; 1312 1313 case IP_RECVRETOPTS: 1314 optval = OPTBIT(INP_RECVRETOPTS); 1315 break; 1316 1317 case IP_RECVDSTADDR: 1318 optval = OPTBIT(INP_RECVDSTADDR); 1319 break; 1320 1321 case IP_RECVIF: 1322 optval = OPTBIT(INP_RECVIF); 1323 break; 1324 } 1325 *mtod(m, int *) = optval; 1326 break; 1327 1328 #if defined(IPSEC) || defined(FAST_IPSEC) 1329 case IP_IPSEC_POLICY: 1330 { 1331 caddr_t req = NULL; 1332 size_t len = 0; 1333 1334 if (m) { 1335 req = mtod(m, caddr_t); 1336 len = m->m_len; 1337 } 1338 error = ipsec4_get_policy(inp, req, len, mp); 1339 break; 1340 } 1341 #endif /*IPSEC*/ 1342 1343 case IP_MULTICAST_IF: 1344 case IP_MULTICAST_TTL: 1345 case IP_MULTICAST_LOOP: 1346 case IP_ADD_MEMBERSHIP: 1347 case IP_DROP_MEMBERSHIP: 1348 error = ip_getmoptions(optname, inp->inp_moptions, mp); 1349 if (*mp) 1350 MCLAIM(*mp, so->so_mowner); 1351 break; 1352 1353 case IP_PORTRANGE: 1354 *mp = m = m_get(M_WAIT, MT_SOOPTS); 1355 MCLAIM(m, so->so_mowner); 1356 m->m_len = sizeof(int); 1357 1358 if (inp->inp_flags & INP_LOWPORT) 1359 optval = IP_PORTRANGE_LOW; 1360 else 1361 optval = IP_PORTRANGE_DEFAULT; 1362 1363 *mtod(m, int *) = optval; 1364 break; 1365 1366 default: 1367 error = ENOPROTOOPT; 1368 break; 1369 } 1370 break; 1371 } 1372 return (error); 1373 } 1374 1375 /* 1376 * Set up IP options in pcb for insertion in output packets. 1377 * Store in mbuf with pointer in pcbopt, adding pseudo-option 1378 * with destination address if source routed. 1379 */ 1380 int 1381 #ifdef notyet 1382 ip_pcbopts(optname, pcbopt, m) 1383 int optname; 1384 #else 1385 ip_pcbopts(pcbopt, m) 1386 #endif 1387 struct mbuf **pcbopt; 1388 struct mbuf *m; 1389 { 1390 int cnt, optlen; 1391 u_char *cp; 1392 u_char opt; 1393 1394 /* turn off any old options */ 1395 if (*pcbopt) 1396 (void)m_free(*pcbopt); 1397 *pcbopt = 0; 1398 if (m == (struct mbuf *)0 || m->m_len == 0) { 1399 /* 1400 * Only turning off any previous options. 1401 */ 1402 if (m) 1403 (void)m_free(m); 1404 return (0); 1405 } 1406 1407 #ifndef __vax__ 1408 if (m->m_len % sizeof(int32_t)) 1409 goto bad; 1410 #endif 1411 /* 1412 * IP first-hop destination address will be stored before 1413 * actual options; move other options back 1414 * and clear it when none present. 1415 */ 1416 if (m->m_data + m->m_len + sizeof(struct in_addr) >= &m->m_dat[MLEN]) 1417 goto bad; 1418 cnt = m->m_len; 1419 m->m_len += sizeof(struct in_addr); 1420 cp = mtod(m, u_char *) + sizeof(struct in_addr); 1421 memmove(cp, mtod(m, caddr_t), (unsigned)cnt); 1422 bzero(mtod(m, caddr_t), sizeof(struct in_addr)); 1423 1424 for (; cnt > 0; cnt -= optlen, cp += optlen) { 1425 opt = cp[IPOPT_OPTVAL]; 1426 if (opt == IPOPT_EOL) 1427 break; 1428 if (opt == IPOPT_NOP) 1429 optlen = 1; 1430 else { 1431 if (cnt < IPOPT_OLEN + sizeof(*cp)) 1432 goto bad; 1433 optlen = cp[IPOPT_OLEN]; 1434 if (optlen < IPOPT_OLEN + sizeof(*cp) || optlen > cnt) 1435 goto bad; 1436 } 1437 switch (opt) { 1438 1439 default: 1440 break; 1441 1442 case IPOPT_LSRR: 1443 case IPOPT_SSRR: 1444 /* 1445 * user process specifies route as: 1446 * ->A->B->C->D 1447 * D must be our final destination (but we can't 1448 * check that since we may not have connected yet). 1449 * A is first hop destination, which doesn't appear in 1450 * actual IP option, but is stored before the options. 1451 */ 1452 if (optlen < IPOPT_MINOFF - 1 + sizeof(struct in_addr)) 1453 goto bad; 1454 m->m_len -= sizeof(struct in_addr); 1455 cnt -= sizeof(struct in_addr); 1456 optlen -= sizeof(struct in_addr); 1457 cp[IPOPT_OLEN] = optlen; 1458 /* 1459 * Move first hop before start of options. 1460 */ 1461 bcopy((caddr_t)&cp[IPOPT_OFFSET+1], mtod(m, caddr_t), 1462 sizeof(struct in_addr)); 1463 /* 1464 * Then copy rest of options back 1465 * to close up the deleted entry. 1466 */ 1467 (void)memmove(&cp[IPOPT_OFFSET+1], 1468 &cp[IPOPT_OFFSET+1] + sizeof(struct in_addr), 1469 (unsigned)cnt - (IPOPT_MINOFF - 1)); 1470 break; 1471 } 1472 } 1473 if (m->m_len > MAX_IPOPTLEN + sizeof(struct in_addr)) 1474 goto bad; 1475 *pcbopt = m; 1476 return (0); 1477 1478 bad: 1479 (void)m_free(m); 1480 return (EINVAL); 1481 } 1482 1483 /* 1484 * following RFC1724 section 3.3, 0.0.0.0/8 is interpreted as interface index. 1485 */ 1486 static struct ifnet * 1487 ip_multicast_if(a, ifindexp) 1488 struct in_addr *a; 1489 int *ifindexp; 1490 { 1491 int ifindex; 1492 struct ifnet *ifp = NULL; 1493 struct in_ifaddr *ia; 1494 1495 if (ifindexp) 1496 *ifindexp = 0; 1497 if (ntohl(a->s_addr) >> 24 == 0) { 1498 ifindex = ntohl(a->s_addr) & 0xffffff; 1499 if (ifindex < 0 || if_indexlim <= ifindex) 1500 return NULL; 1501 ifp = ifindex2ifnet[ifindex]; 1502 if (!ifp) 1503 return NULL; 1504 if (ifindexp) 1505 *ifindexp = ifindex; 1506 } else { 1507 LIST_FOREACH(ia, &IN_IFADDR_HASH(a->s_addr), ia_hash) { 1508 if (in_hosteq(ia->ia_addr.sin_addr, *a) && 1509 (ia->ia_ifp->if_flags & IFF_MULTICAST) != 0) { 1510 ifp = ia->ia_ifp; 1511 break; 1512 } 1513 } 1514 } 1515 return ifp; 1516 } 1517 1518 /* 1519 * Set the IP multicast options in response to user setsockopt(). 1520 */ 1521 int 1522 ip_setmoptions(optname, imop, m) 1523 int optname; 1524 struct ip_moptions **imop; 1525 struct mbuf *m; 1526 { 1527 int error = 0; 1528 u_char loop; 1529 int i; 1530 struct in_addr addr; 1531 struct ip_mreq *mreq; 1532 struct ifnet *ifp; 1533 struct ip_moptions *imo = *imop; 1534 struct route ro; 1535 struct sockaddr_in *dst; 1536 int ifindex; 1537 1538 if (imo == NULL) { 1539 /* 1540 * No multicast option buffer attached to the pcb; 1541 * allocate one and initialize to default values. 1542 */ 1543 imo = (struct ip_moptions *)malloc(sizeof(*imo), M_IPMOPTS, 1544 M_WAITOK); 1545 1546 if (imo == NULL) 1547 return (ENOBUFS); 1548 *imop = imo; 1549 imo->imo_multicast_ifp = NULL; 1550 imo->imo_multicast_addr.s_addr = INADDR_ANY; 1551 imo->imo_multicast_ttl = IP_DEFAULT_MULTICAST_TTL; 1552 imo->imo_multicast_loop = IP_DEFAULT_MULTICAST_LOOP; 1553 imo->imo_num_memberships = 0; 1554 } 1555 1556 switch (optname) { 1557 1558 case IP_MULTICAST_IF: 1559 /* 1560 * Select the interface for outgoing multicast packets. 1561 */ 1562 if (m == NULL || m->m_len != sizeof(struct in_addr)) { 1563 error = EINVAL; 1564 break; 1565 } 1566 addr = *(mtod(m, struct in_addr *)); 1567 /* 1568 * INADDR_ANY is used to remove a previous selection. 1569 * When no interface is selected, a default one is 1570 * chosen every time a multicast packet is sent. 1571 */ 1572 if (in_nullhost(addr)) { 1573 imo->imo_multicast_ifp = NULL; 1574 break; 1575 } 1576 /* 1577 * The selected interface is identified by its local 1578 * IP address. Find the interface and confirm that 1579 * it supports multicasting. 1580 */ 1581 ifp = ip_multicast_if(&addr, &ifindex); 1582 if (ifp == NULL || (ifp->if_flags & IFF_MULTICAST) == 0) { 1583 error = EADDRNOTAVAIL; 1584 break; 1585 } 1586 imo->imo_multicast_ifp = ifp; 1587 if (ifindex) 1588 imo->imo_multicast_addr = addr; 1589 else 1590 imo->imo_multicast_addr.s_addr = INADDR_ANY; 1591 break; 1592 1593 case IP_MULTICAST_TTL: 1594 /* 1595 * Set the IP time-to-live for outgoing multicast packets. 1596 */ 1597 if (m == NULL || m->m_len != 1) { 1598 error = EINVAL; 1599 break; 1600 } 1601 imo->imo_multicast_ttl = *(mtod(m, u_char *)); 1602 break; 1603 1604 case IP_MULTICAST_LOOP: 1605 /* 1606 * Set the loopback flag for outgoing multicast packets. 1607 * Must be zero or one. 1608 */ 1609 if (m == NULL || m->m_len != 1 || 1610 (loop = *(mtod(m, u_char *))) > 1) { 1611 error = EINVAL; 1612 break; 1613 } 1614 imo->imo_multicast_loop = loop; 1615 break; 1616 1617 case IP_ADD_MEMBERSHIP: 1618 /* 1619 * Add a multicast group membership. 1620 * Group must be a valid IP multicast address. 1621 */ 1622 if (m == NULL || m->m_len != sizeof(struct ip_mreq)) { 1623 error = EINVAL; 1624 break; 1625 } 1626 mreq = mtod(m, struct ip_mreq *); 1627 if (!IN_MULTICAST(mreq->imr_multiaddr.s_addr)) { 1628 error = EINVAL; 1629 break; 1630 } 1631 /* 1632 * If no interface address was provided, use the interface of 1633 * the route to the given multicast address. 1634 */ 1635 if (in_nullhost(mreq->imr_interface)) { 1636 bzero((caddr_t)&ro, sizeof(ro)); 1637 ro.ro_rt = NULL; 1638 dst = satosin(&ro.ro_dst); 1639 dst->sin_len = sizeof(*dst); 1640 dst->sin_family = AF_INET; 1641 dst->sin_addr = mreq->imr_multiaddr; 1642 rtalloc(&ro); 1643 if (ro.ro_rt == NULL) { 1644 error = EADDRNOTAVAIL; 1645 break; 1646 } 1647 ifp = ro.ro_rt->rt_ifp; 1648 rtfree(ro.ro_rt); 1649 } else { 1650 ifp = ip_multicast_if(&mreq->imr_interface, NULL); 1651 } 1652 /* 1653 * See if we found an interface, and confirm that it 1654 * supports multicast. 1655 */ 1656 if (ifp == NULL || (ifp->if_flags & IFF_MULTICAST) == 0) { 1657 error = EADDRNOTAVAIL; 1658 break; 1659 } 1660 /* 1661 * See if the membership already exists or if all the 1662 * membership slots are full. 1663 */ 1664 for (i = 0; i < imo->imo_num_memberships; ++i) { 1665 if (imo->imo_membership[i]->inm_ifp == ifp && 1666 in_hosteq(imo->imo_membership[i]->inm_addr, 1667 mreq->imr_multiaddr)) 1668 break; 1669 } 1670 if (i < imo->imo_num_memberships) { 1671 error = EADDRINUSE; 1672 break; 1673 } 1674 if (i == IP_MAX_MEMBERSHIPS) { 1675 error = ETOOMANYREFS; 1676 break; 1677 } 1678 /* 1679 * Everything looks good; add a new record to the multicast 1680 * address list for the given interface. 1681 */ 1682 if ((imo->imo_membership[i] = 1683 in_addmulti(&mreq->imr_multiaddr, ifp)) == NULL) { 1684 error = ENOBUFS; 1685 break; 1686 } 1687 ++imo->imo_num_memberships; 1688 break; 1689 1690 case IP_DROP_MEMBERSHIP: 1691 /* 1692 * Drop a multicast group membership. 1693 * Group must be a valid IP multicast address. 1694 */ 1695 if (m == NULL || m->m_len != sizeof(struct ip_mreq)) { 1696 error = EINVAL; 1697 break; 1698 } 1699 mreq = mtod(m, struct ip_mreq *); 1700 if (!IN_MULTICAST(mreq->imr_multiaddr.s_addr)) { 1701 error = EINVAL; 1702 break; 1703 } 1704 /* 1705 * If an interface address was specified, get a pointer 1706 * to its ifnet structure. 1707 */ 1708 if (in_nullhost(mreq->imr_interface)) 1709 ifp = NULL; 1710 else { 1711 ifp = ip_multicast_if(&mreq->imr_interface, NULL); 1712 if (ifp == NULL) { 1713 error = EADDRNOTAVAIL; 1714 break; 1715 } 1716 } 1717 /* 1718 * Find the membership in the membership array. 1719 */ 1720 for (i = 0; i < imo->imo_num_memberships; ++i) { 1721 if ((ifp == NULL || 1722 imo->imo_membership[i]->inm_ifp == ifp) && 1723 in_hosteq(imo->imo_membership[i]->inm_addr, 1724 mreq->imr_multiaddr)) 1725 break; 1726 } 1727 if (i == imo->imo_num_memberships) { 1728 error = EADDRNOTAVAIL; 1729 break; 1730 } 1731 /* 1732 * Give up the multicast address record to which the 1733 * membership points. 1734 */ 1735 in_delmulti(imo->imo_membership[i]); 1736 /* 1737 * Remove the gap in the membership array. 1738 */ 1739 for (++i; i < imo->imo_num_memberships; ++i) 1740 imo->imo_membership[i-1] = imo->imo_membership[i]; 1741 --imo->imo_num_memberships; 1742 break; 1743 1744 default: 1745 error = EOPNOTSUPP; 1746 break; 1747 } 1748 1749 /* 1750 * If all options have default values, no need to keep the mbuf. 1751 */ 1752 if (imo->imo_multicast_ifp == NULL && 1753 imo->imo_multicast_ttl == IP_DEFAULT_MULTICAST_TTL && 1754 imo->imo_multicast_loop == IP_DEFAULT_MULTICAST_LOOP && 1755 imo->imo_num_memberships == 0) { 1756 free(*imop, M_IPMOPTS); 1757 *imop = NULL; 1758 } 1759 1760 return (error); 1761 } 1762 1763 /* 1764 * Return the IP multicast options in response to user getsockopt(). 1765 */ 1766 int 1767 ip_getmoptions(optname, imo, mp) 1768 int optname; 1769 struct ip_moptions *imo; 1770 struct mbuf **mp; 1771 { 1772 u_char *ttl; 1773 u_char *loop; 1774 struct in_addr *addr; 1775 struct in_ifaddr *ia; 1776 1777 *mp = m_get(M_WAIT, MT_SOOPTS); 1778 1779 switch (optname) { 1780 1781 case IP_MULTICAST_IF: 1782 addr = mtod(*mp, struct in_addr *); 1783 (*mp)->m_len = sizeof(struct in_addr); 1784 if (imo == NULL || imo->imo_multicast_ifp == NULL) 1785 *addr = zeroin_addr; 1786 else if (imo->imo_multicast_addr.s_addr) { 1787 /* return the value user has set */ 1788 *addr = imo->imo_multicast_addr; 1789 } else { 1790 IFP_TO_IA(imo->imo_multicast_ifp, ia); 1791 *addr = ia ? ia->ia_addr.sin_addr : zeroin_addr; 1792 } 1793 return (0); 1794 1795 case IP_MULTICAST_TTL: 1796 ttl = mtod(*mp, u_char *); 1797 (*mp)->m_len = 1; 1798 *ttl = imo ? imo->imo_multicast_ttl 1799 : IP_DEFAULT_MULTICAST_TTL; 1800 return (0); 1801 1802 case IP_MULTICAST_LOOP: 1803 loop = mtod(*mp, u_char *); 1804 (*mp)->m_len = 1; 1805 *loop = imo ? imo->imo_multicast_loop 1806 : IP_DEFAULT_MULTICAST_LOOP; 1807 return (0); 1808 1809 default: 1810 return (EOPNOTSUPP); 1811 } 1812 } 1813 1814 /* 1815 * Discard the IP multicast options. 1816 */ 1817 void 1818 ip_freemoptions(imo) 1819 struct ip_moptions *imo; 1820 { 1821 int i; 1822 1823 if (imo != NULL) { 1824 for (i = 0; i < imo->imo_num_memberships; ++i) 1825 in_delmulti(imo->imo_membership[i]); 1826 free(imo, M_IPMOPTS); 1827 } 1828 } 1829 1830 /* 1831 * Routine called from ip_output() to loop back a copy of an IP multicast 1832 * packet to the input queue of a specified interface. Note that this 1833 * calls the output routine of the loopback "driver", but with an interface 1834 * pointer that might NOT be &loif -- easier than replicating that code here. 1835 */ 1836 static void 1837 ip_mloopback(ifp, m, dst) 1838 struct ifnet *ifp; 1839 struct mbuf *m; 1840 struct sockaddr_in *dst; 1841 { 1842 struct ip *ip; 1843 struct mbuf *copym; 1844 1845 copym = m_copy(m, 0, M_COPYALL); 1846 if (copym != NULL 1847 && (copym->m_flags & M_EXT || copym->m_len < sizeof(struct ip))) 1848 copym = m_pullup(copym, sizeof(struct ip)); 1849 if (copym != NULL) { 1850 /* 1851 * We don't bother to fragment if the IP length is greater 1852 * than the interface's MTU. Can this possibly matter? 1853 */ 1854 ip = mtod(copym, struct ip *); 1855 1856 if (copym->m_pkthdr.csum_flags & (M_CSUM_TCPv4|M_CSUM_UDPv4)) { 1857 in_delayed_cksum(copym); 1858 copym->m_pkthdr.csum_flags &= 1859 ~(M_CSUM_TCPv4|M_CSUM_UDPv4); 1860 } 1861 1862 ip->ip_sum = 0; 1863 ip->ip_sum = in_cksum(copym, ip->ip_hl << 2); 1864 (void) looutput(ifp, copym, sintosa(dst), NULL); 1865 } 1866 } 1867